| Message ID | 20230131134646.9868-1-naush@raspberrypi.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series |
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| Related | show |
Quoting Naushir Patuck (2023-01-31 13:46:46) > The VC4 ISP uses a pipeline bit-depth of 13-bits. The AGC algorithm needs to > know this bit-depth when computing the Y value for the image. > > Instead of hardcoding the VC4 bit-depth in the AGC source code, normalise all > region sums to 16-bits when filling the Statistics structure. AWB and ALSC are > agnostic about pipeline depth, so do not need changing. > > Signed-off-by: Naushir Patuck <naush@raspberrypi.com> > Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> > --- > src/ipa/raspberrypi/controller/rpi/agc.cpp | 11 +++++------ > src/ipa/raspberrypi/raspberrypi.cpp | 18 ++++++++++++------ > src/ipa/raspberrypi/statistics.h | 6 ++++++ > 3 files changed, 23 insertions(+), 12 deletions(-) > > diff --git a/src/ipa/raspberrypi/controller/rpi/agc.cpp b/src/ipa/raspberrypi/controller/rpi/agc.cpp > index 868c30f03d66..ea0c82b5c4c8 100644 > --- a/src/ipa/raspberrypi/controller/rpi/agc.cpp > +++ b/src/ipa/raspberrypi/controller/rpi/agc.cpp > @@ -28,8 +28,6 @@ LOG_DEFINE_CATEGORY(RPiAgc) > > #define NAME "rpi.agc" > > -static constexpr unsigned int PipelineBits = 13; /* seems to be a 13-bit pipeline */ > - > int AgcMeteringMode::read(const libcamera::YamlObject ¶ms) > { > const YamlObject &yamlWeights = params["weights"]; > @@ -586,6 +584,7 @@ void Agc::fetchAwbStatus(Metadata *imageMetadata) > static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, > double weights[], double gain) > { > + constexpr unsigned int maxVal = 1 << Statistics::NormalisationFactorPow2; > /* > * Note how the calculation below means that equal weights give you > * "average" metering (i.e. all pixels equally important). > @@ -593,9 +592,9 @@ static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, > double rSum = 0, gSum = 0, bSum = 0, pixelSum = 0; > for (unsigned int i = 0; i < stats->agcRegions.numRegions(); i++) { > auto ®ion = stats->agcRegions.get(i); > - double rAcc = std::min<double>(region.val.rSum * gain, ((1 << PipelineBits) - 1) * region.counted); > - double gAcc = std::min<double>(region.val.gSum * gain, ((1 << PipelineBits) - 1) * region.counted); > - double bAcc = std::min<double>(region.val.bSum * gain, ((1 << PipelineBits) - 1) * region.counted); > + double rAcc = std::min<double>(region.val.rSum * gain, (maxVal - 1) * region.counted); > + double gAcc = std::min<double>(region.val.gSum * gain, (maxVal - 1) * region.counted); > + double bAcc = std::min<double>(region.val.bSum * gain, (maxVal - 1) * region.counted); > rSum += rAcc * weights[i]; > gSum += gAcc * weights[i]; > bSum += bAcc * weights[i]; > @@ -608,7 +607,7 @@ static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, > double ySum = rSum * awb.gainR * .299 + > gSum * awb.gainG * .587 + > bSum * awb.gainB * .114; > - return ySum / pixelSum / (1 << PipelineBits); > + return ySum / pixelSum / maxVal; > } > > /* > diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp > index cff079bbafb3..1cf7649c3303 100644 > --- a/src/ipa/raspberrypi/raspberrypi.cpp > +++ b/src/ipa/raspberrypi/raspberrypi.cpp > @@ -1154,11 +1154,17 @@ RPiController::StatisticsPtr IPARPi::fillStatistics(bcm2835_isp_stats *stats) co > /* RGB histograms are not used, so do not populate them. */ > statistics->yHist = std::move(RPiController::Histogram(stats->hist[0].g_hist, NUM_HISTOGRAM_BINS)); > > + /* > + * All region sums are based on a 13-bit pipeline bit-depth. Normalise > + * this to 16-bits for the AGC/AWB/ALSC algorithms. > + */ > + constexpr unsigned int scale = Statistics::NormalisationFactorPow2 - 13; > + > statistics->awbRegions.init({ DEFAULT_AWB_REGIONS_X, DEFAULT_AWB_REGIONS_Y }); > for (i = 0; i < statistics->awbRegions.numRegions(); i++) > - statistics->awbRegions.set(i, { { stats->awb_stats[i].r_sum, > - stats->awb_stats[i].g_sum, > - stats->awb_stats[i].b_sum }, > + statistics->awbRegions.set(i, { { stats->awb_stats[i].r_sum << scale, > + stats->awb_stats[i].g_sum << scale, > + stats->awb_stats[i].b_sum << scale }, > stats->awb_stats[i].counted, > stats->awb_stats[i].notcounted }); > > @@ -1168,9 +1174,9 @@ RPiController::StatisticsPtr IPARPi::fillStatistics(bcm2835_isp_stats *stats) co > */ > statistics->agcRegions.init(15); > for (i = 0; i < statistics->agcRegions.numRegions(); i++) > - statistics->agcRegions.set(i, { { stats->agc_stats[i].r_sum, > - stats->agc_stats[i].g_sum, > - stats->agc_stats[i].b_sum }, > + statistics->agcRegions.set(i, { { stats->agc_stats[i].r_sum << scale, > + stats->agc_stats[i].g_sum << scale, > + stats->agc_stats[i].b_sum << scale }, > stats->agc_stats[i].counted, > stats->awb_stats[i].notcounted }); > > diff --git a/src/ipa/raspberrypi/statistics.h b/src/ipa/raspberrypi/statistics.h > index affb7272c963..22a72c94a90d 100644 > --- a/src/ipa/raspberrypi/statistics.h > +++ b/src/ipa/raspberrypi/statistics.h > @@ -30,6 +30,12 @@ using RgbyRegions = RegionStats<RgbySums>; > using FocusRegions = RegionStats<uint64_t>; > > struct Statistics { > + /* > + * All histogram and region based statistics are scaled to a maximum > + * value given by (1 << NormalisationFactorPow2) - 1. > + */ > + static constexpr unsigned int NormalisationFactorPow2 = 16; > + > /* > * Positioning of the AGC statistics gathering in the pipeline: > * Pre-WB correction or post-WB correction. > -- > 2.25.1 >
diff --git a/src/ipa/raspberrypi/controller/rpi/agc.cpp b/src/ipa/raspberrypi/controller/rpi/agc.cpp index 868c30f03d66..ea0c82b5c4c8 100644 --- a/src/ipa/raspberrypi/controller/rpi/agc.cpp +++ b/src/ipa/raspberrypi/controller/rpi/agc.cpp @@ -28,8 +28,6 @@ LOG_DEFINE_CATEGORY(RPiAgc) #define NAME "rpi.agc" -static constexpr unsigned int PipelineBits = 13; /* seems to be a 13-bit pipeline */ - int AgcMeteringMode::read(const libcamera::YamlObject ¶ms) { const YamlObject &yamlWeights = params["weights"]; @@ -586,6 +584,7 @@ void Agc::fetchAwbStatus(Metadata *imageMetadata) static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, double weights[], double gain) { + constexpr unsigned int maxVal = 1 << Statistics::NormalisationFactorPow2; /* * Note how the calculation below means that equal weights give you * "average" metering (i.e. all pixels equally important). @@ -593,9 +592,9 @@ static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, double rSum = 0, gSum = 0, bSum = 0, pixelSum = 0; for (unsigned int i = 0; i < stats->agcRegions.numRegions(); i++) { auto ®ion = stats->agcRegions.get(i); - double rAcc = std::min<double>(region.val.rSum * gain, ((1 << PipelineBits) - 1) * region.counted); - double gAcc = std::min<double>(region.val.gSum * gain, ((1 << PipelineBits) - 1) * region.counted); - double bAcc = std::min<double>(region.val.bSum * gain, ((1 << PipelineBits) - 1) * region.counted); + double rAcc = std::min<double>(region.val.rSum * gain, (maxVal - 1) * region.counted); + double gAcc = std::min<double>(region.val.gSum * gain, (maxVal - 1) * region.counted); + double bAcc = std::min<double>(region.val.bSum * gain, (maxVal - 1) * region.counted); rSum += rAcc * weights[i]; gSum += gAcc * weights[i]; bSum += bAcc * weights[i]; @@ -608,7 +607,7 @@ static double computeInitialY(StatisticsPtr &stats, AwbStatus const &awb, double ySum = rSum * awb.gainR * .299 + gSum * awb.gainG * .587 + bSum * awb.gainB * .114; - return ySum / pixelSum / (1 << PipelineBits); + return ySum / pixelSum / maxVal; } /* diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp index cff079bbafb3..1cf7649c3303 100644 --- a/src/ipa/raspberrypi/raspberrypi.cpp +++ b/src/ipa/raspberrypi/raspberrypi.cpp @@ -1154,11 +1154,17 @@ RPiController::StatisticsPtr IPARPi::fillStatistics(bcm2835_isp_stats *stats) co /* RGB histograms are not used, so do not populate them. */ statistics->yHist = std::move(RPiController::Histogram(stats->hist[0].g_hist, NUM_HISTOGRAM_BINS)); + /* + * All region sums are based on a 13-bit pipeline bit-depth. Normalise + * this to 16-bits for the AGC/AWB/ALSC algorithms. + */ + constexpr unsigned int scale = Statistics::NormalisationFactorPow2 - 13; + statistics->awbRegions.init({ DEFAULT_AWB_REGIONS_X, DEFAULT_AWB_REGIONS_Y }); for (i = 0; i < statistics->awbRegions.numRegions(); i++) - statistics->awbRegions.set(i, { { stats->awb_stats[i].r_sum, - stats->awb_stats[i].g_sum, - stats->awb_stats[i].b_sum }, + statistics->awbRegions.set(i, { { stats->awb_stats[i].r_sum << scale, + stats->awb_stats[i].g_sum << scale, + stats->awb_stats[i].b_sum << scale }, stats->awb_stats[i].counted, stats->awb_stats[i].notcounted }); @@ -1168,9 +1174,9 @@ RPiController::StatisticsPtr IPARPi::fillStatistics(bcm2835_isp_stats *stats) co */ statistics->agcRegions.init(15); for (i = 0; i < statistics->agcRegions.numRegions(); i++) - statistics->agcRegions.set(i, { { stats->agc_stats[i].r_sum, - stats->agc_stats[i].g_sum, - stats->agc_stats[i].b_sum }, + statistics->agcRegions.set(i, { { stats->agc_stats[i].r_sum << scale, + stats->agc_stats[i].g_sum << scale, + stats->agc_stats[i].b_sum << scale }, stats->agc_stats[i].counted, stats->awb_stats[i].notcounted }); diff --git a/src/ipa/raspberrypi/statistics.h b/src/ipa/raspberrypi/statistics.h index affb7272c963..22a72c94a90d 100644 --- a/src/ipa/raspberrypi/statistics.h +++ b/src/ipa/raspberrypi/statistics.h @@ -30,6 +30,12 @@ using RgbyRegions = RegionStats<RgbySums>; using FocusRegions = RegionStats<uint64_t>; struct Statistics { + /* + * All histogram and region based statistics are scaled to a maximum + * value given by (1 << NormalisationFactorPow2) - 1. + */ + static constexpr unsigned int NormalisationFactorPow2 = 16; + /* * Positioning of the AGC statistics gathering in the pipeline: * Pre-WB correction or post-WB correction.